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  <title>Checks if the function has a specified return type</title>
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  <div id="layout-content"><div id="reflectionfunctionabstract.hasreturntype" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">ReflectionFunctionAbstract::hasReturnType</h1>
  <p class="verinfo">(PHP 7, PHP 8)</p><p class="refpurpose"><span class="refname">ReflectionFunctionAbstract::hasReturnType</span> &mdash; <span class="dc-title">Checks if the function has a specified return type</span></p>

 </div>

 <div class="refsect1 description" id="refsect1-reflectionfunctionabstract.hasreturntype-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="modifier">public</span> <span class="methodname"><strong>ReflectionFunctionAbstract::hasReturnType</strong></span>(): <span class="type">bool</span></div>

  <p class="para rdfs-comment">
   Checks whether the reflected function has a return type specified.
  </p>
 </div>


 <div class="refsect1 parameters" id="refsect1-reflectionfunctionabstract.hasreturntype-parameters">
  <h3 class="title">参数</h3>
  <p class="para">此函数没有参数。</p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-reflectionfunctionabstract.hasreturntype-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   Returns <strong><code>true</code></strong> if the function is a specified return type, otherwise <strong><code>false</code></strong>.
  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-reflectionfunctionabstract.hasreturntype-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-5216">
    <p><strong>示例 #1 <span class="methodname"><strong>ReflectionFunctionAbstract::hasReturnType()</strong></span> example</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br /></span><span style="color: #007700">function&nbsp;</span><span style="color: #0000BB">to_int</span><span style="color: #007700">(</span><span style="color: #0000BB">$param</span><span style="color: #007700">)&nbsp;:&nbsp;</span><span style="color: #0000BB">int&nbsp;</span><span style="color: #007700">{<br />&nbsp;&nbsp;&nbsp;&nbsp;return&nbsp;(int)&nbsp;</span><span style="color: #0000BB">$param</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #0000BB">$reflection1&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">ReflectionFunction</span><span style="color: #007700">(</span><span style="color: #DD0000">'to_int'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$reflection1</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">hasReturnType</span><span style="color: #007700">());</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
bool(true)
</pre></div>
    </div>
   </div>

   <div class="example" id="example-5217">
    <p><strong>示例 #2 Usage on built-in functions</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /><br />$reflection2&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">ReflectionFunction</span><span style="color: #007700">(</span><span style="color: #DD0000">'array_merge'</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$reflection2</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">hasReturnType</span><span style="color: #007700">());</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
bool(false)
</pre></div>
    </div>
   </div>
  </p>
  <p class="para">
   This is because many internal functions do not have types specified for their
   parameters or return values. It is therefore best to avoid using this
   method on built-in functions.
  </p>
 </div>


 <div class="refsect1 seealso" id="refsect1-reflectionfunctionabstract.hasreturntype-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="methodname"><a href="reflectionfunctionabstract.getreturntype.html" class="methodname" rel="rdfs-seeAlso">ReflectionFunctionAbstract::getReturnType()</a> - Gets the specified return type of a function</span></li>
   </ul>
  </p>
 </div>


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